L
lysol
My plant is definitely infected. http://www.icmag.com/ic/showthread.php?t=161891
2) If you're using plain tap water to break down your coco, that's a problem. I use a pH adjusted 1/3-1/2 strength complete nutrient solution to break down the coco. (Or flush it, if it's the moist bagged stuff. Bcuzz, etc..) Anytime my problem seemed to be pH related, I had to bring the pH low to compensate for breaking down the coco in 7.0 tap water. At least that is what I have observed.
5.5 feed ph works for me because my ph usually drifts up to 6.0(sometimes higher) after 24 hours.
i wish i knew why it was doing that, i'm using RO water and fox farm nutrients, that's it, no additives. pH after 24 hours is the runoff, not the reservoir. GH users don't get any drift or am i alone?
In most cases, small pH adjustments (0.2 to 0.6 pH units) are easily accomplished by simply changing the type of fertilizer. Large pH adjustments can be time consuming, costly and typically result from infrequent pH monitoring.
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The form of nitrogen in your fertilizer is what causes substrate pH to decrease or increase. Nitrogen is the most important pH-controlling ion because it is the only element required by plants that can be supplied as both a positive cation (ammonium: NH4+) or a negative anion (nitrate: NO3-) and accounts for more than half of the nutrient ions taken up by the plant. Fertilizers high in ammonium have an acidifying effect and cause substrate pH to decrease, and the opposite is true for fertilizers high in nitrate (Table 1).
When ammonium (or other positive cations) is taken up by the plant, a positive charge enters the root. Plants must remain electrochemically neutral, and thus the roots secrete positively charged H+, which reduces the pH (Figure 2). When nitrate (or other negative anions) is absorbed, the roots balance the negative charge by absorbing H+. As more nitrate is absorbed, more H+ is removed from the soil solution, and the substrate pH increases (Figure 3, see page 46).
Urea is a third form of nitrogen that is a common component of fertilizer. Once in the soil or the plant, urea is split into carbon dioxide and ammonium by the urease enzyme produced by microorganisms or the plant. For this reason, urea is considered equivalent to ammonium in respect to effect on substrate pH.
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Water alkalinity is essentially dissolved limestone and if not treated, will lead to problems with high pH such as micronutrient deficiency.
If the concentration of alkalinity in water is zero, the opposite will occur and substrate pH will decrease over time.
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When plants were grown with deionized water, substrate pH decreased over time regardless of fertilizer treatment. Generally, end-of-crop substrate pH increased as the amount of ammonium in the fertilizer decreased.
When plants were grown with high-alkalinity tap water, the opposite occurred and substrate pH increased over time, regardless of fertilizer treatment. Fertilizer treatment did not have as strong an effect on end-of-crop substrate pH as with deionized water. Results indicate the high alkalinity is the primary factor controlling the change in substrate pH.
To clarify, the first sentence is talking about the pH over time. The second sentence is comparing only the data points at the very end of the crop/experiment. You could also say that “end-of-crop substrate pH decreased as ammonium increased”.
I had cal/mag problems in my first coco grow using this 6ml/9ml GH nutes only. Adding a bit of cal-mag (6ml/gallon) seemed to help a bit, but it obviously wasn't the whole issue.
Eventually I measured my well water at 250 ppm, higher than I would have guessed. Another well available to me measured out under 100 ppm, so I switched to that water. POW! happy plants!
its not a ratio problem with the nutrients
the problem is with your water
Could be from either too soft of water or too hard of water.
How is possible to have great results with these different numbers, all growing in coco?
Plants can change the PH themselves.
Plants also can adapt
People use different nutes
There are different kinds of coco, etc..
In nature there is no man standing over the plant with a test kit and drops ;-) the plant still grows.
Yes plants can grow in a variety of conditions, especially in nature. In our indoor setting we can never completely reproduce nature (nor would we want to, lots of plants die in nature for various natural reasons), so we try to take from our knowledge of biochemistry and utilize only the important aspects of nature and do it in the most efficient manner possible.KNNA said:...
If you use it as hydro medium, of course you need to add all the nutes the plants needs, as coco is a near inert medium. Coco coir has a very high cation fixation capacity, as well as very high cation exchangeability. But its neccesary to mantain a equilibrium between the differents cation, otherwise lockouts appear. To manage this, ph control is the key, using all the hydro range (wide range:5,3-6,3, narrow range 5,6-6,1). If you run a ph over 5,8 continously, Ca accumulates in the medium and produces a lot of problems. Flush rids anions easily, but its more difficult wash out cations fixed in the medium.
There are 2 "schools" in coco coir growing: one use ph over 5,8 , add Mg continuosly and flush periodically (the advise of Kapt Krink), while the other use a wider ph range trying to avoid salts accumulation by ph management, without adding CalMg nor flushing...
if your pH keeps rising on its own then there is your problem
get better water
mixing it to a pH of 5.6 on monday, it should read MAYBE 5.7 on thursday. grow/micro/bloom won't fuck with the pH but trying to be clever with additives will...
Can you or anyone else expand on this a bit? Right now I only ever save nute mixes for a few days, but they drift from 5.8 to 6.1 or so, just sitting in a 5 gallon bucket for 24-48 hours. I'm planning on hooking up a 10-15 gallon res, and will be adding airstones. Will this make a difference with the PH drift at all, or is it just because of my tap water?
No access to RO machines around here... might have to look into hooking one up.